package 集合;

import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;

/**
 * @author shy_black
 * @date 2019/8/1 14:04
 * @Description:
 */
public class MainTest {
    public static void main(String[] args) {
        Collection collection;
        ConcurrentHashMap concurrentHashMap;
        ConcurrentMap concurrentMap;
        HashMap<Integer,Integer> map = new HashMap<>();

    }

}
